1. Field of the Invention
The present invention relates to a manufacturing method of a semiconductor device, a semiconductor device, and an electronic device.
2. Description of the Related Art
In recent years, an integrated circuit that uses an SOI (silicon on insulator) substrate replacing a silicon wafer formed by thinly slicing an ingot of single crystal silicon, has been developed. An SOI substrate has a structure in which a thin single crystal silicon layer is provided on an insulating surface. By using this structure, parasitic capacitance between a drain of a transistor and a substrate can be reduced and performance of a semiconductor integrated circuit can be improved.
There are various manufacturing methods of an SOI substrate, and a technique called Smart Cut (registered trademark) is known as a method in which both quality and productivity (throughput) of a formed single crystal semiconductor layer are balanced. In Smart Cut, hydrogen ions are implanted into a single crystal silicon substrate (bond wafer) and then the single crystal silicon substrate is bonded to another substrate (base wafer) at room temperature. Bonding is performed by forming a strong bond by van der Waals force. After that, heat treatment is performed at a temperature of approximately 500° C., so that the single crystal silicon substrate is separated at a region where the hydrogen ions have been implanted, and a single crystal silicon layer is left over another substrate (base wafer).
As an example of a technique of forming a single crystal silicon thin film over a glass substrate by using such Smart Cut, a technique by the present applicants is known (e.g., Patent Document 1: Japanese Published Patent Application No. H11-163363).
In the Patent Document 1, by forming an insulating film over a glass substrate, contamination of a single crystal silicon layer is prevented, and a high-performance semiconductor device is successfully provided.